Mental fatigue resulting from prolonged cognitive training is a serious challenge to performance stability in precision-demanding sports such as shooting. The aim of the present study was to investigate the effects of mental fatigue induced by prolonged imagery on kinematic variables in shooting and to determine the protective role of imagery ability in preserving the integrity of the motor control system. In a repeated measure design, 24 air pistol shooters were selected and divided into two groups based on their MIQ-3 questionnaire scores: high and moderate imagery ability. The intervention consisted of a short-term imagery session (20 trials) and a long term fatigue inducing imagery session (120 trials). Shooting performance was recorded using the SCATT analysis system, and variables stability of hold, aiming accuracy, cleanness of triggering and overall performance were extracted.The results showed that mental fatigue had a significant interactive effect on the variables of aiming accuracy (P=0.008) and cleanness of triggering (P=0.047). In contrast, for the variables stability of hold and overall performance, no significant difference was observed in the pattern of changes between the two groups, and both groups exhibited similar behavior (P>0.05). The findings indicate that high imagery ability specifically protects against the decline of cognitive-technical mechanisms in the face of fatigue but has no effect on physiological fatigue. The lack of decline in overall score despite technical decline in the moderate group suggests the presence of compensatory effort, highlighting the necessity of using microstructural analyses for accurate fatigue detection and personalization of mental training.